The hypothesis of this study is that the severe cases of heart failure seen in cases of peripartum cardiomyopathy are the tip of the iceberg. We postulate that by using these sensitive indices of ventricular contractility, we will be able to find many cases of abnormal ventricular function in asymptomatic patients. Through this study we hope to develop a profile of patients at risk for ventricular dysfunction and gain a better understanding of why these patients develop severe heart failure.